The present invention relates to a lighting and communication system for a confined space.
According to OSHA, a confined space is a space that is large enough for workers to enter and perform certain jobs. It has limited or restricted means for entry or exit and is not designed for continuous occupancy. Confined spaces include tanks, vessels, silos, storage bins, hoppers, vaults, pits, manholes, tunnels, equipment housings, ductwork, pipelines, etc. A confined space may have the potential to contain a hazardous atmosphere, may contain material that has the potential to engulf an entrant, or may contain other hazards.
In many confined spaces, it is desirable to eliminate the possibility of a spark or excessive heat, which could cause an explosion or fire. At the same time, most of the time that workers are in confined spaces, they need some form of artificial lighting, which typically introduces an electrical current that could create a spark or that generates heat that could cause a fire or injure a worker. This is a problem which typically requires the use of electrically intrinsically safe devices which are expensive, heavy, and bulky.
Another problem in confined spaces is that it often is difficult to communicate, due to noise, reduced visibility, cramped surroundings, impeded line-of-sight, and other issues.